The option named mmal-zerocopy until now is used to configure the codec to
generate pictures with MMAL_ENCODING_OPAQUE which in fact is a fake payload
format that just contains handles for pictures allocated on the GPU side.
While this in effect causes a zerocopy mode of pixel data the naming is
potentially misleading because mmal supports another mode called zero_copy. In
this mode the GPU and CPU use shared buffers via the vc_sm kernel module, so
that the buffer data is actually accessible from userspace but no copies are
required when transferring from or to mmal components.
Signed-off-by: Julian Scheel <julian@jusst.de>
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>